The square takes its name from the Palace built by Cardinal Pietro Barbo, then donated in 1560 by Pius IV to the Republic of Venice, which made it the seat of its embassy, which is why it is still called Palazzo Venezia today.

Located between Via del Corso and Via dei Fori Imperiali, Piazza Venezia derives its shape from the renovation of the area for the construction, between the 800s and the 900s, of the Monument to Vittorio Emanuele II.

The grandiose monument, known as the Altar of the Fatherland, was begun in 1885 and completed in 1911. The architectural structure represents an ideal ascending path that, through stairways and terraces, enriched by sculptural groups and bas-reliefs, rises up to the grandiose colonnaded portico surmounted by bronze quadrigas, allegories of the Unity of the Fatherland and Freedom. In 1921, in the crypt designed by Armando Brasini, the body of the Unknown Soldier was buried.

In addition to Palazzo Venezia, the original arrangement of the square has been preserved in Palazzo Bonaparte, where Napoleon's mother, Letizia Ramolino, lived from 1818 until her death.